(a) Field of the invention:
The present invention relates to a key holding member of elongated shape, from one end of which a key is freely hung through connecting metal member and chain and in which a rod of permanent magnet is embedded or to one face of which a sheet of permanent magnet is adhered. When the key holding member is put into its corresponding opening for receiving the key holding member in the key box provided at the front of a hotel or the like after the door of a room is locked by the key held by the key holding member to leave the room absent, the rod of permanent magnet embedded in the key holding member or the sheet of permanent magnet adhered to one face of the key holding member is caused to come close to a reed switch provided in the key box, so that the read switch is rendered operative to close or open an electrical circuit connected to the reed switch so as to turn "on" or "off" a lamp which shows that the room is absent, to keep an electrical circuit for an alarming device closed so as to cause the alarming device to alarm whenever the room is broken into or a fire starts in the room, and to put various electrical equipments furnished in the room to the "off" state relative to their power source, thus keeping the room safe when it is absent.
(b) Brief description of the prior art:
Various types of keys used to lock our room and house are essential to us who are living these days and it is a blow to us if we lose these keys. In order to avoid such case, various measures have been employed. One of the most popular measures is to connect a key through connecting metal member and chain to a plate of appropriate shape which is now often made of plastics. This is intended to always remind us of the key so as to prevent us from losing the key when we go about bringing the key with us after we leave out room or house absent. In other words, this is intended to make extremely smaller the possibility of our losing the key as compared with the case where we bring the key only.
Each of the keys employed in such accommodations as hotel is usually connected to a member of elongated shape, on which a room number is printed. This is also intended to prevent us from losing the key and to always remind us of the presence of the key.
However, these measures are all aimed to attain the objects of preventing us from losing the key, reminding us of the presence of the key, and making the key, which is relatively a small article, easy to handle.